Updated news fragment.

Author: LarsAsplund

docs/news.d/899.feature.rst

@@ -1,4 +1,12 @@
-[Questa/Modelsim] Added support for 3-step flow which is enabled by setting the
-simulation option ``modelsim.three_step_flow`` to ``True``. Extra flags to the ``vopt``
-step can be provided with the simulation flags ``modelsim.vopt_flags`` and
+[Questa/Modelsim] Added support for 3-step flow and the Visualizer debugger.
+
+The 3-step flow is enabled by setting the simulation option ``modelsim.three_step_flow`` to ``True``. Extra
+flags to the ``vopt`` step can be provided with the simulation flags ``modelsim.vopt_flags`` and
 ``modelsim.vopt_flags.gui`` in normal and GUI mode, respectively.
+
+The Visualizer debugger is enabled from the command line using the ``--debugger=visualizer`` option (in
+addition to the ``--gui`` option for GUI mode). The 3-step flow must be enabled for this feature while
+the default ``original`` debugger works with or without the 3-step flow.
+
+Note: There is a bug in Visualizer preventing the normal ``restart`` command from being used. Please use the
+``vunit_restart`` command instead.